Railway car retarder



No v. 18, 1952 Filed Sept. 18, 1951 W. F. MITCHELL RAILWAY CAR RETARDER 2 SHEETS-SHEET l j 1010092509": M44759 f. M/ra /m,

Nov. 18, 1952 w, MlTcHELL, 2,618,364

RAILWAY CAR RETARDER Filed Sept. 18, 1951 2 SHEETS-SHEET 2 la weniox W44 r52 F/V/TCHELL,

Patented Nov. 18, 1952 RAILWAY CARTRETARDER Walter F. Mitchell, Birmingham, Ala, assignor to United States Steel Company,-a corporation of New Jersey Application September 18, 1951, Serial No. 247,179

7 Claims. (01. 188 62) The present invention relates to apparatus for controlling thespeedof; rolling railway equipmen al. 1: c' It is an object of this invention to provide appe tu a a ted to b i st led i a tr kw vf retarding the speed of moving railway equipment or cars on down grade tracks-so as to prevent acceleration to undesirable speeds while the cars are approaching a bumper block, a cushioned car stop or'the like. r j a 1 An example of one form which the invention maytake is described in the following specificationand shown in the accompanying drawings in whichi- Ii Figure l is a plan View;

Figure 2 is aside elevational view partly in sec tion taken on the line II II of Figure 1; p

Figure 3 is an enlarged detailed view taken on theline Ill-III of Figure 1-; V

Figure l is an end view partly in section taken on the line IV-IV of Figure 2; and 1 v Figure 5 showsan enlarged detail view of the linkage system. r

Referring more particularly to the drawings, reference numeral 2 indicates a pit located under of the shaft 36 are journaled in bearings 38 mounted on the two sides of the: base frame 6. .Links .26 are so shaped thatrotation of the shaft J36in the counterclockwise direction, as shown in .46. is mounted in a bracket'48 which is supported at one endby a vtransverse beam 50 secured to frame 6 and at itsrother end by a short structural angle 53 which projects inwardly from the end of the frame'fi. When pressure fluidis apaportion of a downgrade tram trackway l. 1A

fabricated baseframe B is rigidly set in the pit 2, and supports the rails 8 of the trackway 4 above it. Concrete may-be poured around-the outside of the frame 6 to anchor it firmly within the pit. A secondary frame I0 is mounted for pivotal movement within the frame 6 belowthe trackway 4 andintermediate the rails 8. The forward end l2 of the secondary'frame I6 is suspended by means of a pair of depending spaced eye-bolts 14 which are connected, by means of nuts l8, to a transverse supporting beam [6 which is positioned across one end of the base frame 6. The secondary frame is connected for; pivotal movement o'nlthe enact the eye bolt by means'of pins -26, achlof which is carried in a bronze bushing 22 inthe lower endof-each eye bolt. v

. The" rear end of the secondary frame is pivotally connected with and supported by a pairiof spacedangularly shaped links 26 by means of pins 28 whichpass throughbronze bushings 36 carried by each of the links, as best shown in Figure 5. Blocks;34 are we1ded to the frame l0 and are positioned; against the flat sides of the heads of the pivot pins 26 and 28 to prevent the rotation of the pins relative to the frame It]. This assures that the pins will rotate only in the bushings. The other ends of the links 26' are connected with apair of "spaced lever arms 32 which are keyed onto a. rotatable transvrseshaft 36.; The ends plied-to cylinder 46 through fluid supply line 55, the piston rod 44 is ejected therefrom, which action rotates the shaft 36 in a counterclockwise direction to move the links 26 so that the rear end of the frame In is lowered; Conversely, pressure, fluidis supplied to the head end of the cylinder 46 to retract the piston rod within the cylinder and rotate the shaft 36 in the clockwise direction when it is desired to raise the frame 16. Bumpers 52iand'54 are provided adjacent the for- .Ward and rearward end of the frame It! respectively so .asto limit the horizontal movement-of the frame and to absorb any end thrust imparted thereto. J The bumpers .52 and 54 are rigidly mounted onthe base frame 6.. The lever which supports the upper end of the links 26 comprises hubs 56 which are keyed onto the shaft 36 adjacent each end thereof. Each hub is provided with'two spaced apart-projecting arms 58 which have aligned holes 66 in the ends thereof. A pin 62 which is carried by the projections on each of the hubs 56 supports a bushing-64- between the projections. Each of the bushings 64 isformed for slip fit in a bearing seat fi6'inwthe ends of links 26; The design of the supporting-linkagesfor the rearward end 24 of the secondary-frame- I6 is such that the frame islocked intoposition when it is raised. This is accomplished by'having the line of action through the pivotpoints A and B and the'bodyof link 26 on--opposite sides of 'the'center line of the'shaft 36 as-shown in Figure 5. Asthe' load on the. frame H] is increasedrthe torqueiacting through the levers T32 is also increased. This torque acts to pull the link 26 towards the center line of the shaft-36, thusi'locking, its and the framelilinto posi io -1. 1 e c Apair of spaced bearing 68 is mounted on the upper 'surfaceof the. frame J 0 J intermediate its ends to rotatably support a wheel shaft having a pair of rubber-tired Wheels 12 keyed thereto. As shown in Figure 1 the wheels are mounted on the ends of the shaft which projects from each of the two bearings. A brake drum I4 is keyed onto the shaft 10 around its center portion intermediate the bearings 68. As best seen in Figure 3, a brake band 16 is disposed around the brake drum 74 in the conventional manner with one end of the brake band being connected to one end of an adjusting nut 18 while its other end is secured to a bracket support 80 which is mounted on the supporting frame 10 adjacent to the brake drum 14. A link member 82 is pivotally connected at one end to the bracket support 80 adjacent the point to which the end of the brake band is anchored. The opposite end of the link 82 is pivotally connected with a piston rod 84 which projects from a fluid cylinder 86 pivotally mounted on the supporting frame It] adjacent the bracket support 80. A fluid supply line 8'! is provided for furnishing pressure fluid to the cylinder 85. The link 82 is provided with an opening 88 for accommodating a bolt 90 which is pivotally connected with the bracket support 80 and projects upwardly therefrom through the link 82. The projecting portion of the bolt 90 is threaded to accommodate lock nuts 92 thereon. A compression spring 94 is circumferentially mounted on the projecting portion of the bolt 96 with one end bearing on the link 82 and its other end bearing against a washer 96 which is fitted around the bolt 90 adjacent to the lock nut 92.

The tension of the brake hand it around the brake drum M is adjusted by means of the adjusting nut 78 so that the rotation of the wheel shaft H3 is constantly under restraint. When it is desired to release the brake band from the drum 14 in order to allow the wheel shaft to rotate freely, pressure is applied in the fluid cylinder 86 to eject the piston rod 8t which in turn raises the link member 82 to compress the spring 94. The raising action of the link 82 elevates the adjusting nut 18 a sufiicient distance to free the brake band from the brake drum. When it is desired to reapply the restraining action, pressure is released from the cylinder 85 and the link 82 is lowered to normal position by the compressing action of the spring 94.

In operation, when it is desired to retard the speed of railway tram cars travelling over the trackway 4 the secondary platform It] is raised into operating position, as shown in solid lines in Figure 2, by actuating cylinder d6 to retract the piston rod and rotate shaft 36 in the clockwise direction by the lever 42. Rotation of the shaft causes the links 26 to raise the end 24 of the frame ID. When frame I0 is raised into operating position a circumferential portion of each of the wheels 12 projects above the rails 8 a sufficient distance to contact the smooth bottom of a tram car travelling over the trackway 4. As each car passes over the car retarder its bottom contacts the wheels 12 which then bear part of the weight of the car. The moving car turns the wheels 12 and shaft l0 against the restraint created by the brake mechanism. Thus, part of the kinetic energy of the moving car is absorbed and the speed of the car is reduced. In the case of a coupled trip or train of cars, each car will be retarded a given amount as it in turn passes over the retarder until the movement of the train is reduced to a-desirable speed or brought to a stop, as the case may be. If the train is stopped and it is then desired to let it move further down the grade, the set brake can be released by means of applying pressure to the fluid cylinder 86. When it is desired to permit rolling equipment to pass over the car retarder without engaging the wheels 12 the shaft 36 is rotated in the counterclockwise direction to rotate the links 26 and lower the end 24 of the platform In to the position shown in broken lines in Figure 2.

While one embodiment of my invention has been shown and described it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. Apparatus for retarding the movement of a vehicle traveling on a railway trackway which comprises a trackway, rails on said trackway, at least one wheel rotatably mounted belowsaid trackway intermediate the rails thereof with its axis disposed transversely of said trackway, the rim of said wheel being covered with a friction inducing material, a circumferential portion of said wheel projecting above said trackway to contact the bottom of a vehicle traveling thereon, and means for restraining the rotation of said wheel.

2. Apparatus for retarding the movement of a vehicle traveling on a railway trackway which comprises a trackway, rails on said trackway, a shaft rotatably mounted transversely beneath said trackway intermediate the rails thereof, at least one wheel secured on said shaft, the rim of said wheel being covered with a friction-inducing material, a circumferential portion of said wheel projecting above said trackway to contact the bottom of a vehicle traveling thereon, and brake means for restraining the rotation of said shaft.

3. Apparatus for retarding the movement of a vehicle traveling on a railway trackway which comprises a trackway, rails on said trackway, a main supporting frame rigidly disposed beneath said trackway intermediate the rails thereof, a secondary frame mounted for pivotal movement within said main frame, a shaft rotatably journaled on said secondary frame transversely of said trackway, at least one wheel having a rim of friction-inducing material secured on said shaft, a circumferential portion of said wheel projecting above the rails of said trackway when said secondary platform is in operating position, brake means operatively connected with said shaft for restraining the rotation thereof, and means carried by said main frame for raising and lowering said secondary frame to thereby raise and lower said circumferential portion above and below the rails of said trackway.

4. Apparatus for retarding the movement of a vehicle traveling on a railway trackway which comprises a trackway, rails on said trackway, a main supporting frame rigidly disposed beneath said trackway intermediate the rails thereof, a secondary frame disposed within said main frame, said secondary frame being pivotally connected at one end to said main frame, a rotatable transverse shaft carried by said main frame above the end of said secondary frame remote from said pivoted end, a pair of spaced lever arms keyed to said shaft, a pair of angularly shaped links each attached at one end to one of said lever arms and depending therefrom to a pivotal connection with the end of said secondary frame remote from said pivoted end whereby said secondary frame is raised and lowered upon rotation of said shaft, means for rotating said shaft,

a wheel shaft rotatably journaled on said secondary frame intermediate said pivoted end and said link-supported end transversely of said trackway, at least one wheel having a rim of frictioninducing material secured on said wheel shaft, a circumferential portion of said wheel projecting above the rails of said trackway when said secondary frame is in operating position, and brake means operatively connected with said wheel shaft for restraining the rotation thereof.

5. Apparatus for retarding the movement of a vehicle traveling on a railway trackway as defined in claim 4 characterized by said means for rotating said shaft including a lever arm keyed onto said shaft, a fluid cylinder having a piston rod slidably fitted therein pivotally mounted on said main frame adjacent said shaft, the outer end of said piston rod being pivotally connected with said last named lever arm, and fluid-supply lines for said fluid cylinder.

6. Apparatus for retarding the movement of a vehicle traveling on a railway trackway as defined in claim 5 characterized by bumper bars mounted transversely in said main frame adjacent the ends of said secondary frame for limiting the longitudinal movement thereof.

'7. Apparatus for retarding the movement of a WALTER F. MITCHELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 878,113 Breslauer et a1 Feb. 4, 1908 FOREIGN PATENTS Number Country Date 432,039 Germany 1926 955,176 France 1950 

